Fetch attachments to a message. 

    Set observer with setObserver method to get process and complete events

*/

void NmAttachmentManager::fetchAttachments(

        const NmId &mailboxId, 

        const NmId &folderId, 

        const NmId &messageId,

        QList<NmId> &messagePartIds)

{

    // cancel old fetch operation, Does nothing if fetch not ongoing

    // We don't wan't to cancel message fetching operation, because

    // it might still be finishing.

    if (!mMsgFetchOperation) {

        cancelFetch();

    }

    if (messagePartIds.count() > 0) {

        mFetchOperation = mUiEngine.fetchMessageParts(

            mailboxId,

            folderId,

            messageId,

            messagePartIds);

    }

    if (mFetchOperation) {

        mAttaId = 0;

        mIsFetching = true;

        QObject::connect(mFetchOperation, SIGNAL(operationCompleted(int)),

                this, SLOT(attachmentFetchCompleted(int)));

        QObject::connect(mFetchOperation, SIGNAL(operationProgressChanged(int)),

                this, SLOT(changeProgress(int)));

    }

}

/*!

    Fetch all message parts to a message. Fetches also message part data structure,

    if not fetched already.

      If earlier fetch operation exist it is cancelled and deleted.

    Set observer with setObserver method to get process and complete events

*/

void NmAttachmentManager::fetchAllMessageParts(

        const NmId &mailboxId, 

        const NmId &folderId, 

        const NmId &messageId)

{

    fetchMsg = mUiEngine.message(mailboxId,folderId,messageId);

    // Check if we have part data structure.    

    if (fetchMsg->childParts().count() == 0 &&

        fetchMsg->fetchedSize() < fetchMsg->size()) {

        // cancel old fetch operation, Does nothing if fetch not ongoing

        cancelFetch();

        // Fetch the message.

        mMsgFetchOperation = mUiEngine.fetchMessage(

            fetchMsg->envelope().mailboxId(),

            fetchMsg->envelope().folderId(),

            fetchMsg->envelope().messageId());

        mAttaId = 0;

        mIsFetching = true;

        if (mMsgFetchOperation) {

            QObject::connect(mMsgFetchOperation,

                    SIGNAL(operationCompleted(int)),

                    this,

                    SLOT(messageFetched(int)));

        }

    }

    else {

        messageFetched(NmNoError);

    }

}

/*!

    if (mMsgFetchOperation && mMsgFetchOperation->isRunning()) {

        mMsgFetchOperation->cancelOperation();

    }

    Used by message fetch operation

*/

void NmAttachmentManager::messageFetched(int result)

{

    QObject::disconnect(mFetchOperation,

                SIGNAL(operationCompleted(int)),

                this,

                SLOT(messageFetched(int)));

    if (result == NmNoError) {

        // Reload message

        fetchMsg = mUiEngine.message(

            fetchMsg->envelope().mailboxId(),

            fetchMsg->envelope().folderId(),

            fetchMsg->envelope().messageId());

        if (fetchMsg) {

            QList<NmId> partIds;

            NmMessagePart *part;

            foreach (part, fetchMsg->childParts()) {

                if (part->size() > part->fetchedSize()) {

                    partIds.append(part->partId());

                }

            }

            if (partIds.count() > 0) {

                fetchAttachments(

                    fetchMsg->envelope().mailboxId(),

                    fetchMsg->envelope().folderId(),

                    fetchMsg->envelope().messageId(),

                    partIds);

            }

            else {

                mFetchObserver->fetchCompleted(result);

            }

        }

        else {

            mFetchObserver->fetchCompleted(NmNotFoundError);

        }

    }

    else {

        mFetchObserver->fetchCompleted(result);

    }

}

/*!